dear phil, I am trying to write a book that you may find interesting, it's a take on an old premise that has never been seen before.
It's a series of stories about time travel, which all take place in the same setting, but with different characters perspectives, kind of like sin city.
but here is where it becomes unique, it deviaters in every way from how the subject is usually treated:
1: time travel is for everybody (who can afford it):
in most time travel stories, use of the technology is either heavily regulated, or only available to a select few, but here, traveling to, and thereby changing, the past is a technology widely available on the free market.
2. the setting with time travel does not have events which are unalterable, yet it does:
in most stories, you either cannot kill Hitler, or you can, but doing so deletes all future events along your timeline, and overwrites them with a new series of events that follow from the point of deviation.
But in my setting, all timelines with the same set of natural laws coexist exist as complete, predetermined, unalterable, looping entities within a single multiverse, where the last unique point in every timeline, where the universe is crushed into a singularity, is followed by first unique point in the timeline, when the singularity begins to expand again, this happens twice in every given timeline, and in between these points are the two points which all timelines share, that is, at the point of the singularity itself.
so the moment you travel back in time, you are actually entering a previous point in another timeline that is identical up the predetermined point in the timeline where you have warped in, at which point you become a part of the predetermined future of that timeline, unless one of your predetermined actions within it is to warp back in time again, in which case you disappear from it, and into a previous point in another, or into it's future, in which case you skip your existence within the timeline, until the future point at which you reappear again.
3. killing Hitler can lead to only good things!
every time travel story that allows the past to be changed agrees that doing so can only produce a future that punishes the traveler, either by inducing some paradox that threatens to destroy spacetime itself, or by producing only futures which the traveler finds less preferable than the future they came from (looking at you, stein's gate).
but in this setting, it has become common knowledge that changing the future in the past is actually MORE likely to produce a preferable future, than any action you commit in the present (you are already changing the future at this moment, you know?).
For when you change the future in the present, you have less information, and less resources, than when you alter the future via the past, however, it's not exactly as safe a bet as is commonly thought, as adding your present self into a point in time where you didn't exist before, is adding a whole new variable to that timeline's equation, especially if your past self also occupies that point in time.
But it's still pretty damn safe, and MUCH safer than any futures you can create in the present, things CAN go wrong, of course, but the ONLY contributing factor is the actions you take in the past, and the fact that you are committing them in the past itself, is NEVER a factor in determining futures (spacetime has no brain, is not sentient, and cannot recognize, nor judge, nor punish, any "timecrimes" that have been committed against it).